Feedline System · Common-Mode Control
The 3500W Maxi Line Isolator
Half of what you hear as noise never came in through the antenna. It came in on the outside of the coax braid, walked past the tuner, and climbed into the receiver. A current-mode choke is the part that stops it.
The Maxi is the high-power member of the family: multi-core, multi-turn ferrite construction, rated 3500 watts PEP, covering 1 to 61 MHz. Built for amplifier stations, high-duty-cycle digital work, and any installation where the feedline runs long or close to the house.
The Build
| Power rating | 3500 W PEP (500 W above 60 MHz) |
| Frequency range | 1 to 61 MHz |
| Choking impedance | 500 to 5000 ohms across 1 to 60 MHz |
| Common-mode attenuation | 20 to 38 dB, depending on band |
| Insertion loss | Approximately 0.25 dB |
| Connectors | SO-239 female, in and out |
| Enclosure | 12 in long, 2 in diameter |
| Made in | United States |
Do You Need One?
Every Greyline feedline kit ships with slip-on bead choking already included, and for many stations that is enough. The Maxi is for operators who want more: amplifier power, heavy digital duty cycle, a long coax run, a noisy neighborhood, or simply the last few dB.
Running 500 watts or less? The 500W Mini Line Isolator is the right part and costs less.
Not sure which choke your station needs? Call us at 435-200-4902. Tell us your power, your feedline length, and what your noise floor is doing, and we will tell you honestly whether you need this one, the Mini, or neither.
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